Reagents to study Wnt signaling

Reagents to study Wnt signaling can be obtained from several
distributors or commercial vendors. In cases where reagents are not
available, we would be happy to help , but otherwise we refer you to
distributors. We have no commercial interests in those distributors or
vendors, but they are professionals, can provide you with products of
guaranteed quality and with the necessary background information.
Reagents like purified Wnt proteins, antibodies to Wnts or to
b-catenin, TOPflash reporter constructs and Wnt expression constructs
can be obtained from commercial sources (R&D systems, Abcam, Cell
Signaling, Upstate, or Transduction Laboratories)
and easily traced by a websearch. The Wnt homepage does not include
advertisements for commercial products or direct links to vendor
catalogues.

This page is frequently updated. If you find anything that is
published and missing on this site, alert me. If cannot find
information you are looking for, then it is most likely unavailable.
Specifically, beyond the Wnt-producing cells that are listed, there are
no other ones available. We are trying to express other Wnts, with
various degrees of success, but more work needs to be done before these
are useful. Note that reagents not made in our own lab should
be requested from the original sources. This is common practice in the
Biomedical research community and avoids propriety issues.

A great resource of cDNA clones for the Wnt genes themselves, generously provided by Drs. Marian Waterman and David Virshup. Each of the human Wnt genes has been cloned as a cDNA into expression vectors as a Gateway based library. For those who want to study mouse Wnt gene activity, be assured that the mouse/human homologs are similar enough (sometimes even identical in protein sequence) to have similar activity.

Antigen

From

Name

There are good antibodies to detect beta-catenin either on
Western Blots or by staining (Transduction labs). There is also a
monoclonal antibody to the non-phosphorylated ("activated") form of b-catenin (Van
Noort, 2002) available from Upstate. Cell Signaling and R&D
systems sell monoclonal and polyvalent
antibodies to several mammalian Wnt proteins, including Wnt3A
and to Wnt signaling components.

Note: Our lab is not able to send out the anti-Dishevelled or
anti-Axin antibodies anymore. Because of the availability of the
monoclonal antibody to Wingless (see above), we have not
maintained supplies of the rabbit anti-wingless antibody and this is
not available.

Fly stocks

Most of the Drosophila mutant and transgenic lines made in the Nusse lab are available through the Bloomington Stock Center, under these numbers:

It has been notoriously difficult to generate useful antibodies to
vertebrate Wnt proteins. Several groups have made antibodies to
peptides or Wnt-GST fusion proteins.These sera work in Western blots or
immunoprecipitations but usually only in extracts of cells that are
engineered to over-express Wnts by transfections. In general, these
sera do not detect endogenous Wnt proteins in cell extracts, nor do
they detect Wnt proteins in tissues by staining techniques. Hence,
there are few data on Wnt protein distribution in intact vertebrate
animals.

In Drosophila however, the situation is different. There are good
antisera to two Drosophila Wnt proteins: Wingless and DWnt-3/5. It is clear why these proteins are better immunogens: they
both contain long inserts in the proteins (compared to other Wnt
proteins) and it has been shown that these inserts are the antigenic
determinants (unpublished data, Nusse Lab). A mouse monoclonal Neumann
C, et al.)to the Wingless insert works well in staining and in
Western blot experiments and is available from the Developmental
Studies Hybridoma Bank at The University of Iowa.

It seems therefore that one successful strategy to get better sera
is to use non-conserved parts of Wnt proteins. By generating fusion
proteins (we like GST fusions) and by multimerizing the inserts, one
might be able to get a useful antiserum. Note that all Wnt proteins are
less conserved around the sites of the Wingless and DWnt-3/5 inserts. These domains are
also, in general, good sites for the insertion of epitopes (myc, FLAG),
as we found out. Possibly, these domains stick out of the otherwise
highly structurally constrained Wnt proteins and are therefore better
accessible to antibodies. In addition, the Wingless and DWnt-3/5
inserts are not-conserved and are better recognized as foreign by the
mammalian immune system.

Note however that because these antigenic domains in Wingless and
DWnt-3/5 are not conserved, the antibodies to these proteins will not
recognize any other Wnt.

Other good sites for inserting epitopes in Wnts are close to the
amino-terminus.